Working Time Society consensus statements: Evidence-based effects of shift work and non-standard working hours on workers, family and community.

Working time arrangements that require shift work or other non-standard working hours have significant potential to encroach on time that is highly valued for family, social and leisure activity. This can often result in workers experiencing poorer work-family or work-life balance. Based on an extensive literature search and expert knowledge, primary risk factors were identified including shift work; long, irregular and unpredictable working hours; and work on evenings and weekends (in combination and independent of shift work). On the other hand, flexibility, in the form of adequate worker control over work schedules, may be a protective factor. In addition, workers experiencing excessive work-life conflict are likely to reduce their working hours, reflecting a reciprocal relationship between working hours and work-life balance. Workers' families are also affected by shift work and non-standard working hours. Parents' shift work is associated with poorer emotional and developmental outcomes for their children, and to a greater likelihood of risky behavior in adolescence. Additionally, the risk of separation or divorce is increased, especially for parents working night shifts. Due to relationships such as those above, the consequences of shiftwork and non-standard working hours on family and social life are largely dependent on a complex interaction between specific work schedules, other aspects of work organization, and family and individual worker characteristics. This article provides an overview of current evidence regarding the relationships between working time arrangements and various social and family variables, and concludes with shift scheduling and intervention recommendations to improve work-life balance and social well-being.

Daytime Effect of Monochromatic Blue Light on EEG Activity Depends on Duration and Timing of Exposure in Young Men.

Growing evidence suggests an alerting effect of monochromatic blue light on brain activity. Little is known about the moderation of those effects by timing and duration of exposure. The present electroencephalography (EEG ) study examined such moderations on delta, theta, alpha1, alpha2, and beta EEG bands. A counterbalanced repeated-measures design was applied. The 16-hr daytime period was divided into three sessions: 07:00-12:20, 12:20-17:40, and 17:40-23:00 (timing of exposure). Two light conditions comparable in luminance but differing in wavelength were applied, namely polychromatic white light and monochromatic blue light (460 nm). There were two durations of exposure-the shorter one lasting 30 min and the longer one lasting 4 hrs. Thirty male students participated in the study. Four factors analyses of variance (ANOV As, for light conditions, timing of exposure, duration of exposure, and brain area) were performed on each EEG band. Results indicated an alerting effect of short exposure to monochromatic blue light at midday and in the evening, which was demonstrated by a decrease in lower frequency bands (alpha1, delta, and theta, respectively). Long exposure to blue light may have a reverse effect, especially in the morning and at midday, when increases in lower frequency bands (theta in the morning and theta and alpha1 at midday) were observed. It can be concluded that the daytime effect of monochromatic blue light on EEG activity depends on timing and duration of exposure.

Shift schedule, work-family relationships, marital communication, job satisfaction and health among transport service shift workers.

OBJECTIVES: Existing research has documented that shiftwork consequences may depend on the shift system parameters. Fast rotating systems (1-3 shifts of the same kind in a row) and day work have been found to be less disruptive biologically and socially than slower rotating systems and afternoon and night work. The aim of this study was to compare day workers and shift workers of different systems in terms of rotation speed and shifts worked with regard to work-family and family-work positive and negative spillover, marital communication style, job satisfaction and health. MATERIAL AND METHODS: Employees (N = 168) of the maintenance workshops of transportation service working different shift systems (day shift, weekly rotating 2 and 3­shift system, and fast rotating 3-shift system) participated in the study. They completed the Work- Family Spillover Questionnaire, Marital Communication Questionnaire, Minnesota Job Satisfaction Questionnaire and the Physical Health Questionnaire (a part of the Standard Shiftwork Index). RESULTS: The workers of quicker rotating 3-shift systems reported significantly higher scores of family-to-work facilitation (F(3, 165) = 4.175, p = 0.007) and a higher level of constructive style of marital communication (Engagement F(3, 165) = 2.761, p = 0.044) than the workers of slower rotating 2-shift systems. There were no differences between the groups of workers with regard to health and job satisfaction. CONCLUSIONS: A higher level of work-family facilitation and a more constructive style of marital communication were found among the workers of faster rotating 3-shift system when compared to the workers of a slower rotating 2-shift system (afternoon, night). This may indicate that the fast rotating shift system in contrary to the slower rotating one is more friendly for the work and family domains and for the relationship between them. Int J Occup Med Environ Health 2017;30(1):121-131.

Collective narcissism moderates the effect of in-group image threat on intergroup hostility.

Results of 4 experiments demonstrated that under in-group image threat collective narcissism predicts retaliatory intergroup hostility. Under in-group criticism (vs. praise) collective narcissists expressed intention to harm the offending out-group but not other, nonoffending out-groups. This effect was specific to collective narcissism and was replicated in studies that accounted for the overlap between collective narcissism and individual narcissism, in-group positivity (in-group identification, blind and constructive patriotism), social dominance orientation, and right wing authoritarianism. The link between collective narcissism and retaliatory intergroup hostility under in-group image threat was found in the context of national identity and international relations and in the context of a social identity defined by university affiliation. Study 4 demonstrated that the relationship between collective narcissism and intergroup hostility was mediated by the perception of in-group criticism as personally threatening. The results advance our understanding of the mechanism driving the link between collective narcissism and intergroup hostility. They indicate that threatened egotism theory can be extended into the intergroup domain.

Bright light effects on ultradian rhythms in performance on hemisphere-specific tasks.

Ultradian rhythms in indices of brain hemisphere activity and in cognitive performance have been found in numerous studies. Asymmetry of these rhythms with regard to phase and frequency have also been documented in some studies. There is some evidence that bright light can affect ultradian rhythms of arousal state and vigilance. A study on unilateral exposure to bright light has demonstrated more pronounced effects of bright light on the right hemisphere. The aim of this study was to examine whether daytime intermittent bright light could affect parameters of ultradian rhythms in performance speed on hemisphere-specific tasks, and whether the effect of bright light was symmetric for the rhythms in performance on hemisphere-specific tasks presented laterally. A counter-balanced, within-subject research design was applied. The performance of 15 participants on hemisphere-specific tasks exposed laterally was measured every 30 min starting at 08:00 h and ending at 20:30 h in intermittent bright light (IBL, pulses of 15 min of 4000 lux light regularly interspersed between 45 min of background light levels of 300 lux) and in ordinary room light (ORL) conditions (300 lux). Individual time series data were subjected to cosinor analysis. General linear model analyses (the factors were: level of processing, visual field, and the task) were performed on the rhythms' parameters. There was a substantial lengthening of the rhythms' periods in IBL conditions for performance speed on spatial tasks and an increase in amplitude of the rhythms of performance speed for spatial tasks in both visual fields and for verbal tasks in the left visual field in the IBL conditions when compared to the ORL conditions. The results showed that the schedule of light exposure affected ultradian rhythms of hemisphere-specific tasks differently and that the right hemisphere seems to be more "sensitive" to light than the left hemisphere.

Daytime intermittent bright light effects on processing of laterally exposed stimuli, mood, and light perception.

Little is known about intermittent bright light (IBL) exposure during the daytime on oscillations in human performance and mood. The aims of this study were to determine whether the applied regime of IBL can differentially influence the daily oscillations of processing of laterally exposed stimuli, as well as the daily course of alertness and affective state, and the participants' perception of light conditions. A counter-balanced, within-subject study design was applied. Performance and mood of 20 student volunteers were measured every 30 min starting at 08:00 h and ending at 20:30 h in IBL and ordinary room light (ORL) conditions. Near to statistical significance, effects of the IBL regime on performance (i.e., main effect on speed of verbal logical task, and interactive effect of light conditions and measurement time on daily oscillations in speed of processing of spatial tasks) and mood (i.e., interactive effect of bright light and measurement time on global vigor assessment) were found. An assessment of IBL conditions as significantly less comfortable and natural and more glaring when compared to ORL conditions draws attention to the importance of participants' perception of the light, which may affect the application of bright light in real life situations.

Ultradian and asymmetric rhythms of hemispheric processing speed.

Daily changes in cognitive performance have been documented, both in time of day/effect paradigm studies and in time-isolation studies. However, in both types of studies, phenomena such as the "post-lunch dip" have been found that were difficult to explain in terms of theoretical backgrounds. These phenomena may suggest ultradian rhythms in cognitive performance. A number of studies have also shown ultradian and asymmetric rhythms in activity indices of the brain hemispheres. The aim of this study was to test three hypotheses: the first two assumed that there is a significant ultradian frequency in a component of the endogenous rhythm of processing speed, and the third assumed that the ultradian endogenous rhythms of the processing speed (encoding and recognition) of stimuli addressed to the left brain hemisphere differ in period length from those addressed to right hemisphere. During a 24 h constant-routine experiment, the memory performance of 30 participants was measured eight times (every 2.5-3 h), starting at 06:30 h. Parallel sets of words and pictures were shown to subjects in a random order in either the left or the right visual field on a computer screen. The participants pressed one of two buttons in response to the picture or word, or when answering a question concerning the meaning of a presented stimulus. Cosinor analysis was applied to individual time series data. Two significant ultradian components were found in a majority of the time series. Dominant periods were analyzed using three factor ANOVA. The results showed an asymmetry between both hemispheres in the frequency of ultradian rhythms in encoding speed.

The impact of night work on subjective reports of well-being: an exploratory study of health care workers from five nations.

OBJECTIVE: To carry out a survey data collection from health care workers in Brazil, Croatia, Poland, Ukraine and the USA with two primary goals: (1) to provide information about which aspects of well-being are most likely to need attention when shiftwork management solutions are being developed, and (2) to explore whether nations are likely to differ with respect to the impacts of night work on the well-being of workers involved in health care work. METHODS: The respondents from each nation were sorted into night worker and non-night worker groups. Worker perceptions of being physically tired, mentally tired, and tense at the end of the workday were examined. Subjective reports of perceived felt age were also studied. For each of these four dependent variables, an ANCOVA analysis was carried out. Hours worked per week, stability of weekly work schedule, and chronological age were the covariates for these analyses. RESULTS: The results clearly support the general proposal that nations differ significantly in worker perceptions of well-being. In addition, perceptions of physical and mental tiredness at the end of the workday were higher for night workers. For the perception of being physically tired at the end of a workday, the manner and degree to which the night shift impacts the workers varies by nation. CONCLUSIONS: Additional research is needed to determine if the nation and work schedule differences observed are related to differences in job tasks, work schedule structure, off-the-job variables, and/or other worker demographic variables.

The impact of night work on subjective reports of well-being: an exploratory study of health care workers from five nations

OBJETIVO: Coletar dados de pesquisa de profissionais da saúde no Brasil, Croácia, Polônia, Ucrânia e Estados Unidos com duas metas principais: (1) proporcionar informações quanto a aspectos do bem-estar que mais provavelmente precisam de atenção durante a elaboração de soluções administrativas para os turnos de trabalho e (2) examinar a existência de possíveis diferenças entre os países quanto ao impacto do trabalho no bem-estar de profissionais da saúde. MÉTODOS: Os respondentes de cada um dos países estudados foram divididos em dois grupos de profissionais: período noturno e período não-noturno. Verificou-se a percepção dos profissionais quanto ao cansaço físico, cansaço mental e tensão ao final da jornada de trabalho. Relatos subjetivos sobre a percepção da idade sentida também foram estudados. Foi feita uma análise ANCOVA para cada uma destas quatro variáveis. Horas trabalhadas por semana, estabilidade do horário semanal de trabalho e idade cronológica foram as co-variáveis usadas nestas análises. RESULTADOS: Os resultados dão evidente respaldo à proposição geral de que há diferenças consideráveis da percepção de bem-estar entre os países. Além disso, a percepção de cansaço físico e cansaço mental ao final da jornada de trabalho é maior entre os profissionais do período noturno. Difere entre os países, a percepção do cansaço físico ao final da jornada de trabalho, a maneira e o grau do impacto do turno noturno para os profissionais de saúde. CONCLUSÕES: Fazem-se necessários outros estudos para determinar se as diferenças observadas entre os países e esquemas de trabalho guardam relação com diferenças de funções no trabalho, estrutura dos horários de trabalho, variáveis externas ao trabalho e/ou outras variáveis demográficas dos profissionais.

Personal age and assessment of work stress in Polish nurses.

Workers' perception of age and work stress was examined within the context of aging and work. Nurses from selected hospitals in a large Polish town completed the Survey of Health Care Professionals to assess their personal age and on-the-job and off-the-job stressors. The assessment of work performance, effort, and abilities associated with work demands and tiredness after the workday was compared between groups of subjects differing in the magnitude and direction of discrepancies between felt age and chronological age. The results showed that, compared to others, nurses feeling older than their chronological age assessed themselves as putting forth the highest effort to meet their work demands, reported more tiredness after the workday, and reported the lowest work abilities.